Field of the Invention
The present invention relates to a portable terminal device capable of identifying an image processing device that a user wishes to use from among a plurality of image processing devices such as multi-functional digital combined machines referred to as multi function peripherals (MFPs), a communication system including the portable terminal device and the plurality of image processing devices, and a communication method and a communication program carried out in the system.
Description of the Related Art
A technique has been already known in which the portable terminal device including a smartphone, a tablet terminal, and the like and the image processing device such as the aforementioned MFP are mutually connected using a wireless local area network (LAN), Bluetooth (registered trademark), or another wireless communication unit, where an action instruction such as printing output is given to a certain image processing device from the portable terminal device. In this case, an image processing device to which the action instruction is given needs to be selected from a list of a plurality of communicable image processing devices displayed on the portable terminal device.
In recent years, a technique that simplifies operation for selecting the image processing device has been employed in such a manner that a user of the portable terminal device touches his/her portable terminal device on an image processing device (brings his/her portable terminal device closer to an image processing device) to which the user wishes to give the action instruction among the plurality of image processing devices as described above.
Meanwhile, JP 2011-120144 A has proposed a technique that detects the strength of a wireless communication radio wave to identify the image processing device, thereby simplifying the selection of the image processing device.
In the technique disclosed in JP 2011-120144 A described above, however, the image processing device with the maximum strength of radio wave is selected. Accordingly, in such a situation that there are several image processing devices closely arranged to each other and a user approaches the image processing devices from a distance, there is a problem in that a different image processing device than the image processing device that the user wishes to use is selected in some cases, forcing the user to reselect the appropriate image processing device in this case.
For example, in a situation where two image processing devices are installed side by side, when the two image processing devices are located at substantially the same distances from the user, the image processing device that the user intends to use does not always match the image processing device with the maximum strength of radio wave.
In addition, the image processing device closer to the user typically has a larger strength of radio wave. However, it is difficult in many cases to walk straight to the image processing device that the user wishes to use in an office or the like because of a layout of desks and partitions and accordingly, the image processing device with a large strength of radio wave, which is positioned closest to the user is not every time the image processing device that the user intends to use.